An electronic device such as a personal computer and an expansion unit are designed to be connected to each other by mating an electrical connector provided on the electronic device with an electrical connector provided on the expansion unit. Generally, the electrical connector provided on a side of the expansion unit and the electrical connector provided on a side of the electronic device are collectively referred to as a “docking connector.”
In the docking connector, it is important that the contacts of the electrical connector provided on the side of the expansion unit and the contacts of the electrical connector provided on the side of the electronic device are correctly aligned with each other so that proper electrical connection there between is ensured. An example of a docking connector that ensures proper contact alignment is shown in FIG. 6 (see JP11-288760A). FIG. 6 shows a docking connector 101 consisting of a first connector 110 that mates with a second connector 120. The first connector 110 is mounted on a circuit board provided on a side of a personal computer (not shown) and comprises an insulating first housing 111 and a plurality of contacts (not shown). A pair of positioning guide pins 112 protrudes from a mating surface at ends of the first housing 111. The positioning guide pins 112 are constructed so that the positioning guide pin 112 on one end of the first housing 111 has a larger diameter than the positioning guide pin 112 on the other end of the first housing 111.
The second connector 120 is mounted on a circuit board provided on a side of an expansion unit (not shown) and comprises an insulating second housing 121 and a plurality of contacts (not shown). A pair of guide bushes 122 into which the positioning guide pins 112 of the first connector 110 are inserted are provided at ends of the second housing 121. Power supply contacts (not shown) through which a relatively large current flows and signal contacts (not shown) through which a relatively small current flows are generally provided on both the first and second connectors 110, 120. When the positioning guide pins 112 are inserted into the guide bushes 122 during the mating of the first connector 110 with the second connector 120, any positional deviation between the first connector 110 and the second connector 120 is absorbed, so that it is possible to accurately align all of the signal contacts (not shown) and power supply contacts (not shown) with each other.
FIG. 7 shows another example of an electrical connector that is provided on a side of an expansion unit. FIG. 7 shows an electrical connector 201 having an insulating housing 210 that extends in a direction of length (left-right direction in FIG. 7). The housing 210 comprises a housing base 211 that extends in the direction of length. A mating member 212 protrudes upward from the housing base 211 and extends in the direction of length. The mating member 212 mates with a mating connector (not shown) that is provided on a side of a personal computer and has a pair of mating recessed members 212b (only the front-side mating recessed members 212b are shown in the figure) in front and back thereof. One of the mating recessed members 212b is provided on each side of a partition wall 212a. A pair of positioning guides 213 that protrude upward with respect to a mating surface of the mating member 212 (i.e., the upper-end surface of the mating member) are provided on either end of the housing base 211 in the direction of length.
A plurality of signal contacts 221 are provided on front and rear surfaces of each of the mating recessed members 212b. A plurality of power supply contacts 222 are provided on front and rear surfaces of each of the mating recessed members 212b in positions that are separated by a specified interval from the respective rightmost-end of the signal contacts 221 in the direction of length. The signal contacts 221 are electrically connected to signal lines (not shown) of a circuit board (not shown), and the power supply contacts 222 are electrically connected to power supply lines (not shown) of a circuit board (not shown). In the electrical connector 201 shown in FIG. 7, when a conductive piece M such as a clip enters an interior of one of the mating recessed members 212b of the mating member 212, the signal contacts 221 and/or the power supply contacts 222 may be shorted by the conductive piece M, which can damage the components of the docking connector.